RNA interference in ageing research--a mini-review.

BACKGROUND The search for genetic mechanisms affecting life-span and ageing represents an important part of ageing research, especially since the discovery of single-gene mutations with dramatic effects on these traits. Due to its relative ease of use and its power to specifically target arbitrary genes, RNA interference (RNAi) has rapidly been adopted as a technique for silencing gene expression. The feasibility of genome-wide RNAi screens potentially much simplifies the identification of novel ageing-related genes. OBJECTIVE In a review of applications of RNAi in ageing research with a focus on the model organisms Caenorhabditis elegans and Drosophila melanogaster and discussing recent technical developments, we aim to highlight the current and future impact of this technology in the field. METHOD We show how RNAi has successfully been used to complement classic mutant studies. Moreover, we discuss the novel opportunities and challenges of an application of RNAi in genome-wide screens in D. melanogaster, which has become possible with the recent availability of a comprehensive transgenic RNAi library for the fly. We highlight, in particular, how the flexible control of RNAi induction can support the study of dynamic processes like ageing through specific experiments and the development of matching computational methods. In an overview of complementary approaches we discuss the challenge of extracting insight from the high-dimensional measurement datasets that are required for the study of dynamic effects and interaction dependencies. CONCLUSION RNAi has emerged as a powerful tool for the study of ageing, allowing the further characterization of the roles of specific genes in the ageing process as well as the efficient identification of new genes implicated. RNAi has contributed to our understanding of age-related diseases especially by making genes amenable to manipulation for which mutants were not easily available. Recent developments enable genome-wide screens with unprecedented temporal and spatial control of RNAi induction. Specific RNAi time-course experiments provide an opportunity for the analysis of high-resolution gene expression profiles capturing the dynamics of ageing-relevant processes and gene interactions. Research exploiting new avenues opened by the growing RNAi toolbox will considerably contribute to the next steps in researching the genetics of ageing and age-related diseases.